Blood Clotting Assignment Answers…

1) Roles of the clotting components Platelets: Form a plug at the site of injury to slow bleeding. Prothrombin: - Gets converted into an active protein called “thrombin”.

1) Continued… Calcium ions (Ca2+): Used to help turn prothrombin into thrombin Also used, later, to help turn fibrinogen into fibrin. Thrombin: - Acts to start forming the clot by turning fibrinogen into fibrin.

1) Continued… Fibrinogen: Gets converted into fibrin (by thrombin). Forms a network of threads that closes off the injury. Plasmin: - Breaks down the clot once the damage has healed.

2) Which components are in a clot? The clot will end up being made up of platelets and fibrin.

3) Why do clots appear red? Clots often trap some red blood cells (erythrocytes), giving them a red colour.

4) Summarize the clotting process